Secondary glaucoma: clinical guidelines

List of Abbreviations

IOP – intraocular pressure

AQH – aqueous humor

GON – glaucomatous optic neuropathy

ONH – optic nerve head

VEP – visual evoked potentials

ICD-10 – International Classification of Diseases 10th Revision

NRR – neuroretinal rim

OCT — optical coherence tomography (optical examination of the anterior and posterior segments of the eye using a computer analyzer)

VF – visual field

APL — anteroposterior length of the eyeball

RNFL – retinal nerve fiber layer

ACA – anterior chamber angle

CCT – central corneal thickness

CCDS – ciliochoroidal detachment

ERG – electroretinography

EP – electrophysiological studies

C/D — cup-to-disc ratio

Terms and Definitions

Ocular biomicroscopy is a method of in vivo visual examination of the optical media and tissues of the eye based on creating contrast between illuminated and non-illuminated areas, performed using a slit lamp and, if necessary, additional diagnostic lenses (e.g., for fundus biomicroscopy).

Intraocular pressure (IOP) is the pressure of the fluid inside the eye, resulting from the balance between aqueous humor production, trabecular and uveoscleral outflow, and episcleral venous pressure, which maintains the shape of the eye and ensures a constant supply of circulating nutrients and normal trophism of intraocular tissues.

Glaucomatous optic neuropathy (GON) is an optic nerve pathology caused by elevated IOP, characterized by the progressive loss of retinal ganglion cells and their axons, leading to structural and functional damage of the optic nerve, visual impairment, and blindness.

Gonioscopy is a method of visual examination (inspection) of the iridocorneal angle (ICA) performed using a slit lamp and a goniolens (gonioscope).

Goniotomy is a surgical intervention in which tissue obstructing the aqueous humor outflow is removed from the ICA area under visual control (using a goniolens) to restore the anterior outflow pathway.

Gonisynechia is an adhesion in the iridocorneal angle of the eye between the iris root and the cornea.

Optic disc (OD) – the site where retinal ganglion cell axons exit the eyeball.

Neuroretinal rim (NRR) is the area between the optic disc margin and the margin of the excavation, where the bulk of the retinal ganglion cell axons project.

Needling – a surgical technique for mechanical revision of a filtration bleb using a hypodermic needle on a syringe.

Optical coherence tomography (OCT) is a diagnostic, non-invasive, contactless method for in vivo visualization, qualitative, and quantitative analysis of the morphological features of fundus structures, based on the principle of light interferometry.

Ocular hypertension is an elevation in IOP in the absence of characteristic glaucomatous changes in the optic disc, retinal nerve fiber layer, and visual field (VF) defects.

Ophthalmoscopy – an instrumental method for examining the fundus and its structures.

Tonometry – an instrumental method for measuring IOP level, the value of which is determined by analyzing eye deformation data caused by a tonometer and expressed in millimeters of mercury (mmHg).

Perimetry is a method for examining the visual fields.

Visual field – the set of spatial points simultaneously visible to the eye with a fixed gaze.

Refractory glaucoma is a form of the disease with a severe, persistent course, characterized by resistance and often unresponsiveness to standard treatments.

Sinulectomy / trabeculectomy – a surgical intervention aimed at creating an additional outflow pathway for aqueous humor from the eyeball directed beneath the sclera and conjunctiva.

Scotoma – a visual field defect independent of peripheral boundaries.

Retinal nerve fiber layer (RNFL) is a layer of the retina consisting of the axons of retinal ganglion cells.

Stabilized and unstabilized glaucoma are terms indicating the absence or presence of negative dynamics in the state of the optic disc, visual fields, anteroposterior diameter (APD) of the eye, and patient refraction during follow-up examinations. When assessing the dynamics of the glaucomatous process, the level of IOP and its compliance with the "target" value are also taken into account.

Standard automated perimetry – automated threshold static perimetry evaluating the visual field using a white stimulus on a white background.

Anterior chamber angle (ACA) is the space between the corneoscleral region and the anterior surface of the iris.

"Target" intraocular pressure – the maximum permissible pressure at which glaucoma does not progress: visual functions do not decline, GON does not progress, and the eyeball does not stretch.

Optic disc excavation is a depression in the optic disc of various shapes and sizes, normally accounting for no more than 0.3 of the disc diameter (physiological cup).

Electrophysiological studies are methods for examining the function of the optic nerve, retina, and visual areas in the cerebral cortex.

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1. Brief information on the disease or condition

1.1 Definition of the disease or condition

Secondary glaucoma is a group of diseases that are a complication or consequence of various eye disorders (trauma, tumors, intraocular inflammation) or the effects of various drugs, causing an elevation in intraocular pressure. Secondary glaucoma is characterized by a wide variety of etiological factors, pathogenetic mechanisms, and clinical manifestations.

1.2 Etiology and pathogenesis of the disease or condition (group of diseases or conditions)

According to etiology, secondary glaucoma in children is subdivided into the following groups [1-18]:

• inflammatory (post-uveitic) glaucoma;

• phacogenic glaucoma;

• aphakic glaucoma;

• neovascular glaucoma;

• traumatic glaucoma;

• postoperative glaucoma;

• neoplastic glaucoma;

• drug-induced glaucoma.

Inflammatory glaucoma develops in uveitis, keratouveitis, and sclerouveitis due to impaired outflow of aqueous humor (AH) through the trabecular meshwork caused by increased viscosity of the anterior chamber fluid due to the influx of proteins and inflammatory cells from blood vessels, inflammation and edema of the trabecular meshwork, edema and thickening of the iris and ciliary body, formation of gonisynechiae, etc., or as a result of pupillary or malignant block caused by the formation of pupillary or appositional iridolenticular synechiae.

Phacogenic glaucoma occurs due to impaired aqueous humor outflow caused by lens dislocation (phacotopic glaucoma), lens swelling (phacomorphic glaucoma), or the breakdown and release of lens fibers into the anterior chamber (phacolytic glaucoma).

Aphakic glaucoma develops after lens removal (congenital cataract, etc.), especially in the first months of a child's life.

Neovascular glaucoma is the result of the closure of the iridocorneal angle by connective tissue with newly formed blood vessels of the iris (rubeosis) arising due to hypoxia, often combined with chronic dilation of the native vessels or retinal neovascularization of various etiologies, which is accompanied by the production of angiogenic factors. In childhood, it is most commonly observed in the terminal stage of Coats disease, familial exudative vitreoretinopathy, retinal angiomatosis, and long-standing extensive rhegmatogenous or tractional retinal detachment.

Traumatic glaucoma develops against the background of mechanical injuries, thermal and chemical burns of the eyeball, and can occur at any time after the trauma, including the remote period. The causes of secondary glaucoma can be diverse: hyphema, hemophthalmos, damage to the filtration meshwork, formation of epithelial cysts, gonisynechiae, damage to scleral vessels.

Postoperative glaucoma (excluding aphakic) occurs after corneal transplantation, vitreoretinal surgery. Most often, the IOP elevation is temporary, but it can transform into persistent secondary glaucoma.

Neoplastic glaucoma develops primarily as a result of the growth of neoplasms inside the eye or orbit. It is more commonly observed in the late stages of tumor growth in the ciliary body and iris. It can displace the iris root and cause ICA blockade or directly affect the trabecular meshwork. It often occurs in the late stages of retinoblastoma.

Drug-induced glaucoma in childhood is most often caused by the local and/or systemic use of glucocorticoids. There is a decrease in aqueous humor outflow due to the deposition of glucocorticoid metabolites (dihydrocortisols) in trabecular cells; polymerized glycosaminoglycans in the trabecular meshwork (normally depolymerized by lysosomal hyaluronidase, whereas glucocorticoids stabilize lysosomal membranes); the formation of an actin "network" in the extracellular matrix due to increased expression of fibronectin by glucocorticoids and decreased activity of tissue plasminogen activator; and "clogging" of the trabeculae due to glucocorticoid inhibition of phagocytosis, including by trabecular endothelial cells. There is also a genetic predisposition to the hypertensive effect of glucocorticoids.

1.3 Epidemiology of the Disease or Condition

Evaluating the incidence and prevalence of secondary glaucoma in children is difficult due to varying classifications and diagnostic criteria, as well as a relative scarcity of epidemiological studies. The frequency of post-uveitic glaucoma depends on the clinical features and course of uveitis, disease duration, and treatment administered, ranging from 14% to 47% of cases according to various studies [4-6, 8, 10, 15, 16]. Secondary glaucoma develops in 9.7% – 20.2% of children who have undergone congenital cataract extraction [2, 3, 11, 18]. Among childhood glaucomas, glaucoma associated with acquired diseases accounts for 42.6% of cases [14], of which post-traumatic accounts for 6%, postoperative for 2%, neoplastic for 1%, while aphakic glaucoma, considered separately, accounts for 11%–18% [14, 19]. Glaucoma caused by anterior chamber angle recession occurs in 15 per 100,000 children [12]. Elevated IOP occurs in 1/3 of children prescribed glucocorticoids [17].

1.4 Features of Coding the Disease or Condition

H40.3 – Post-traumatic secondary glaucoma

H40.4 – Secondary glaucoma due to inflammatory eye disease

H40.5 – Secondary glaucoma due to other eye diseases

H40.6 – Drug-induced secondary glaucoma

H40.8 – Other glaucoma

H40.9 – Unspecified glaucoma

H42.8 – Glaucoma in other diseases classified elsewhere

1.5 Classification of the disease or condition

There is no unified classification of secondary glaucomas in children. Secondary glaucoma in children is classified by etiology (see section 1.2), pathogenesis, level of intraocular pressure, degree of visual field changes and specific optic disc changes, as well as by clinical course (dynamics of visual functions) [5, 12, 20, 21].

By IOP level (Table 1):

Table 1.

Classification scheme of IOP levels in glaucoma

By the degree of visual field changes and optic disc damage (Table 2):

Table 2.

Classification scheme of glaucoma stages

By clinical course (Table 3):

Table 3.

Classification scheme of glaucoma by the nature of the disease course

By gonioscopic findings:

• open-angle

• closed-angle

1.6 Clinical presentation of the disease or condition

Anamnesis, complaints, and clinical manifestations of secondary glaucoma depend on the etiology of the underlying disease, etiopathogenesis, and the degree of secondary glaucoma compensation.

Complaints (in young children, reported by parents):

• corneal syndrome – photophobia, lacrimation, blepharospasm (may be absent);

• enlargement of the eye and cornea in size (when glaucoma manifests at the age under 3–5 years);

• periodic blurring (edema phenomena), followed by persistent corneal opacity;

• decreased vision (can be detected in older children);

• eye pain (in younger children, behavioral changes: poor sleep, irritability, loss of appetite).

It should be noted that secondary glaucoma is sometimes outwardly asymptomatic, patients and their parents do not present characteristic complaints, and the disease is detected during a follow-up examination for the underlying disease.

The main clinical signs of secondary glaucoma in children are:

• elevated IOP level (see section 1.5);

• development of corneal edema and opacity;

• increase in corneal diameter and stretching of the limbus (when glaucoma manifests at the age under 3–5 years);

• deepening or shallowing of the anterior chamber (normally 2.75–3.5 mm in the center);

• development of glaucomatous optic atrophy (with cupping and thinning of the peripapillary nerve fiber layer and retinal ganglion cell layer);

• increase in the sagittal axis of the eyeball compared to age norms;

• formation of scleral thinnings bulging as staphylomas/

In unilateral cases, asymmetry in the severity of the listed signs (sagittal length, corneal diameter, refraction enhancement, optic disc cupping) is important.

There are differences in the manifestation of these clinical signs depending on the etiology of secondary glaucoma, as well as in children of various ages.

In the absence of intraocular pressure compensation, stabilization of glaucomatous optic neuropathy, and halting the stretching of the eyeball membranes, the course of secondary glaucoma is progressive, leading to irreversible blindness.

2. Diagnostics, medical indications and contraindications for diagnostic methods

The diagnosis of secondary glaucoma is established based on the analysis of complaints, disease history, results of clinical and instrumental ophthalmological examinations: IOP elevation above the target level and detection of signs of glaucomatous optic neuropathy.

Early diagnosis aims to detect initial manifestations of atrophic processes in the optic disc and retinal nerve fiber layer, and in young children, signs of eye stretching caused by elevated IOP.

In children with secondary glaucoma manifesting under the age of 3–5 years and the development of a classical clinical picture of hydrophthalmos, diagnosing the disease is not particularly difficult. With later development of secondary glaucoma, diagnosis can present significant difficulties due to the absence or mild expression of characteristic symptoms, the time-stretched development of the pathological process, difficulties in assessing the state of the optic nerve, tonometry data due to opaque, scar-altered or thickened cornea, media opacities, and optic nerve changes resulting from the underlying disease. The diagnosis of secondary glaucoma must be based on a comprehensive analysis of data.

2.1 Complaints and Anamnesis

Comments: it is important to determine possible predisposing factors for the occurrence of secondary glaucoma (diseases and injuries of the eyeball, presence of systemic body diseases, local or systemic use of glucocorticoids); attention should also be paid to external symptoms of secondary glaucoma and the dynamics of visual functions (see section 1.6 - "complaints").

2.2 Physical Examination

Physical examination is uninformative.

Patients are referred for a general somatic examination and to specialized experts prior to surgical treatment.

2.3 Laboratory Diagnostics

Laboratory diagnostic tests for secondary glaucoma are not currently used; scientific research is ongoing.

2.4 Instrumental Diagnostics

Comments: in children older than 3–5 years, visometry is performed using charts (Orlova, Sivtsev and Golovin, Landolt rings, etc.); at a younger age, it is assessed approximately by presenting objects of different sizes.

In the early stage of glaucoma and in patients with low visual acuity, it may not change significantly.

Comments: when glaucoma develops at an early age and remains uncompensated in children, eye stretching occurs and myopic refraction is often formed (due to uneven stretching of the eye membranes). Accordingly, an increase in clinical refraction can be one of the symptoms of glaucoma non-compensation.

Currently, retinoscopy remains the gold standard method for refractometry in young children. At the same time, it is successfully complemented by instrumental methods, including portable refractometers. The undeniable advantage of refractometers is the ability to accurately determine the astigmatism meridian, including when examining a child under general anesthesia.

Comments: to monitor IOP, it is recommended to use the Maklakov applanation tonometer (the tonometry standard in the RF), the Goldmann applanation tonometer (the global tonometry standard), or various types of non-contact tonometers. The so-called Icare rebound tonometer appears convenient for children, allowing the measurement of true IOP without local anesthesia, including in young children in various body positions.

Many modern methods of "instrumental" tonometry are prone to measurement errors, usually tending to overestimate intraocular pressure (IOP) values. These errors are largely associated with the age-related specific features of the mechanical properties of the cornea, which change even further with the development of buphthalmos. Therefore, if contradictory IOP values are obtained or their reliability is in doubt, it is advisable to resort to applanation tonometry using the Maklakov tonometer.

In infants and young children, IOP figures may not reflect the true clinical picture of the disease, because the stretching of the eye compensates for its elevation. Therefore, the characteristics of intraocular pressure must be considered in conjunction with ocular morphometry.

When analyzing tonometry data, absolute IOP figures, diurnal fluctuations, and—in unilateral disease—the difference in intraocular pressure between the eyes are taken into account. Diurnal fluctuations in IOP levels, as well as asymmetry between fellow eyes in healthy individuals, generally range within 2–3 mmHg and only in rare cases reach 4–6 mmHg.

Pt – tonometry measurements when IOP is measured with a contact Maklakov tonometer, most commonly using a 10 g weight.

P₀ – true IOP – tonometry measurements when IOP is measured by most modern methods (Goldmann tonometry, pneumotonometry, Icare tonometry, etc.).

The statistical normal range for true IOP (P₀) is from 10 to 21 mmHg, and for tonometric IOP (Pt) it is from 12 to 25 mmHg.

Criteria for selecting the "target" IOP for an individual patient have not currently been established. Approximate characteristics of the upper limit of "target" intraocular pressure in patients with various stages of glaucoma are given in Table 4.

Table 4.

Characteristics of the upper limit of "target" intraocular pressure in glaucoma patients

Due to the fact that tonometry data are influenced by corneal thickness and diameter, as well as changes in its viscoelastic properties—including those resulting from the underlying disease (scars, dystrophy, etc.)—it is advisable to take these parameters into account. Specifically, in cases of a thickened, edematous cornea, IOP tonometry readings may be underestimated, while in the presence of corneal scars, they may be overestimated due to reduced corneal rigidity [22].

• The adequacy of "target" IOP values in a specific patient is determined during follow-up monitoring (stabilization or progression of the glaucomatous process). Ultrasound pachymetry A03.26.011.001 is recommended for all patients with secondary glaucoma in order to correctly interpret tonometry results [12].

Level CLevel 5Level of recommendation evidence C (reliability level of evidence – 5).

Comments: the average corneal thickness in the optical zone (central corneal thickness – CCT) in children aged 5–15 years is 529 ± 0.034 µm [23]. Corneas are conventionally classified as thin when CCT is ≤ 520 µm, normal (> 521 < 580 µm), and thick ≥ 581 µm. Tonometry data in eyes with a CCT different from normal require correction (Table 5).

Table 5.

Approximate correction factors for determining the level of intraocular pressure

Measurement of corneal thickness can be performed using ultrasound pachymetry A03.26.011.001, anterior segment OCT A03.26.019.001 (optical examination of the anterior segment using a computerized analyzer), optical biometry of the eye A05.26.007, and a number of other methods, the results of which differ somewhat from each other and cannot be compared "directly".

It should be taken into account that CCT increases from 1 to 11 years of age, and then stabilizes. CCT in boys is approximately 5 µm greater than in girls [24], varies slightly among different ethnic groups depending on the time of day and ongoing local hypotensive therapy, and is influenced by contact lens wear, whereas correction formulas have been developed for normal corneas (without structural changes).

Comments.

Conjunctiva. In secondary glaucoma with compensated and subcompensated IOP, the state of the conjunctiva is most often unchanged. With persistent as well as sudden marked elevation of IOP, congestive injection of the eyeball is observed.

In the presence of filtering blebs (after surgical interventions), attention should be paid to their size, wall thickness, degree of vascularization, and cystic changes.

Cornea. High IOP may cause corneal edema, which resolves after IOP normalization.

In infants and young children with prolonged uncompensated IOP, the corneal diameter increases, causing breaks and cracks in the endothelium and Descemet's membrane in the form of single and then multiple Haab striae. Due to impaired barrier function, aqueous humor penetrates into the corneal stroma, causing edema and subsequent corneal clouding. The limbus also stretches, initially superiorly and subsequently in all quadrants.

Anterior chamber. Normally, the depth of the anterior chamber in the pupillary area is 2.75–3.5 mm. In children with secondary glaucoma, deepening of the anterior chamber is possible (due to stretching of the eyeball in children who develop secondary glaucoma in the first 3–5 years of life, and in some cases of post-traumatic and aphakic glaucoma). In cases of peripheral anterior synechiae, pupillary block, or malignant glaucoma, the anterior chamber may be irregular or shallow. The transparency of the aqueous humor must also be assessed (presence of exudate, blood, pigment, silicone oil).

Iris. In infants and young children with uncompensated glaucoma and eye enlargement, atrophic changes in the iris occur: the pattern smooths out, atrophy of the pupillary ruff develops, crypts become less pronounced, blood vessels become visible (necessitating differentiation from neovascularization), mydriasis appears, and the light reflex is reduced. In patients with neovascular glaucoma, new blood vessels proliferate on the surface of iris, ectropion uveae develops, along with pupillary rigidity and mydriasis.

Attention should be paid to the presence of peripheral anterior synechiae, granulomas, cysts, iris tumors, and iridocorneal contact with angle closure, which are risk factors, or—once the diagnosis is established—the pathogenetic mechanisms of IOP elevation.

Lens. Attention should be paid to the size (lens thickness increases during swelling—phacomorphic glaucoma, and decreases during dissolution of lens material—phacolytic glaucoma), shape, and position of the lens (subluxation, dislocation into the anterior chamber or vitreous body); phacodonesis is also noted.

Comments: it is necessary to assess the drainage zone—the presence and extent of goniosynechiae, neovascularization, fibrous membranes, anterior chamber angle recession, deposition of exudate, blood, fibrin, pigment, and silicone oil microbubbles.

Gonioscopy may be supplemented by ocular biomicrophotography A03.26.005 (for example, using RetCam).

Gonioscopy is not indicated for patients with inflammatory processes of the ocular surface and cannot be performed in the presence of severe corneal opacities, hyphema, opaque exudate in the anterior chamber, or peripheral anterior synechiae (iridocorneal contact).

Comments. One of the main causes of visual function loss in children with secondary glaucoma is the development of glaucomatous optic neuropathy, which requires a detailed characterization of optic disc changes. The difficulty lies in the frequent inability to visualize fundus structures due to media opacities caused by the underlying disease.

Glaucoma is characterized by atrophic changes in the optic disc, manifested by discoloration of atrophic areas, as well as enlargement and deformation of the optic disc cupping.

When examining the optic disc, quantitative and qualitative assessment of the following parameters must be performed.

Quantitative assessment of the optic disc:

• optic disc size;

• cup-to-disc ratio (CDR);

• neuroretinal rim (NRR) to disc ratio

Qualitative assessment of the optic disc:

• shape, height, and color of the neuroretinal rim, a tendency toward its thinning or absence (rim excavation);

• decolorization of atrophic optic disc areas;

• shift of the vascular trunk.

Optic disc size. The average optic disc size ranges from 1.9 to 2.8 mm². Small optic discs are defined as those with an area of less than 1.5 mm², medium as 1.51 to 2.5 mm², and large as >2.51 mm². In myopia, the optic disc may increase slightly (by 1.2±0.15%) for each diopter of ametropia. The larger the optic disc, the larger the cup-to-disc ratio and neuroretinal rim. Accordingly, a large excavation in a large optic disc may be physiological, whereas a small excavation in a small optic disc may be the result of glaucomatous damage, significantly complicating the ophthalmoscopic diagnosis of this pathology.

Cup-to-disc ratio. Physiological cupping of the optic disc typically has a horizontally oval shape: the horizontal diameter is longer than the vertical by approximately 8%. An enlarged physiological excavation with a large disc size is more often round. Normally, the excavation is symmetrical in both eyes. In 96% of cases, the cup-to-disc ratio is within 0.3 disc diameters. In the early stage of glaucoma, there are often no clear distinctions between physiological and glaucomatous cupping.

Enlargement of cupping in glaucoma usually occurs in all directions, but most frequently vertically, due to the thinning of the neuroretinal rim in the superior and inferior sectors of the optic disc, which is associated with the structural features of the lamina cribrosa.

When examining a patient with elevated intraocular pressure, the following principle should be observed: the larger the excavation, the higher the probability that it is glaucomatous.

Neuroretinal rim. As the glaucomatous process develops, the width of the neuroretinal rim gradually decreases, which can be uniform around the entire circumference, local marginal, or combined. Glaucoma is also characterized by atrophic changes in the neuroretinal rim. Clinically, they manifest as discoloration of neuroretinal rim areas, most frequently in the temporal zone.

Peripapillary atrophy—thinning/destruction of the chorioretinal tissue around the optic disc. In glaucoma, the prevalence of peripapillary atrophy is higher, especially on the nasal side of the disc.

In secondary glaucoma, possible changes in the optic disc due to the underlying disease (edema, atrophy) should be taken into account; during ophthalmoscopy, attention should be paid to the presence of ischemic and neovascularization zones, as well as retinal neoplasms.

Photographic documentation is useful for recording the condition of the retina and optic disc.

Comments: The study is feasible provided the child has sufficient intellectual development and object vision.

Of importance is the evaluation of the visual field using both static (static perimetry) and kinetic stimuli. This method allows for the detection of even minimal defects in both the central and peripheral visual fields, significantly increasing the diagnostic and monitoring efficacy of early and advanced secondary glaucoma in adolescents. The parameters subject to evaluation include the position of the peripheral borders of the visual field, the presence of absolute and relative scotomas, and the boundaries of the blind spot. When evaluating the results of static automated perimetry, indices such as mean deviation (MD) and pattern standard deviation (PSD) are also used.

In the advanced stage, an acceptable alternative may be visual field testing using kinetic stimuli to determine the peripheral boundaries of the visual field.

When evaluating perimetry results in patients with secondary glaucoma, possible visual field changes due to the underlying disease should be considered.

Comments: the study is possible with sufficient transparency of the optical media.

With OCT in secondary glaucoma, it is possible to detect, record, and quantitatively assess a complex of objective morphometric data that increase as the disease progresses:

• increase in optic disc excavation dimensions (depth, width, volume);

• decrease in the thickness of the retinal nerve fiber layer in the peripapillary zone;

• decrease in the width of the neuroretinal rim;

• a decrease in the thickness of the ganglion cell layer and the ganglion cell complex.

During initial and follow-up evaluation of the above parameters, the influence of the underlying disease on them should be assessed. In the absence of other causes, their dynamic deterioration is an important sign of secondary glaucoma progression.

When intraocular pressure is normalized in children with glaucoma, regression of optic disc changes may be observed: a decrease in excavation size and an increase in neuroretinal rim dimensions.

Comments. A non-contact method superior in resolution to ultrasound scanning of the anterior segment, it allows evaluation of the structure, measurement, and recording of the condition of the corneal layers, iris, and iridocorneal angle parameters.

Comments. When intraocular pressure is uncompensated, progressive stretching of the eye coats causes impaired blood supply, metabolic, and biochemical processes in the retina and optic nerve. This leads first to compensatory activation and then to a decrease in the bioelectrical activity of the retina recorded during electroretinography.

Performing electroretinography before and after normalization of intraocular pressure makes it possible to assess the state of the retina and optic nerve, the dynamics of changes, and predict the final functional outcomes. Registration of a supernormal electroretinogram simultaneously with high intraocular pressure values indicates a short period of hypertension and a favorable functional outcome. High intraocular pressure values with a low electroretinogram amplitude are characteristic of more pronounced pathological changes in the retinal structure and a poorer functional prognosis. After normalization of intraocular pressure, the electroretinogram amplitude decreases over 3–6 months to values corresponding to the stage of the disease and the preservation of the retinal neuroepithelium. With persistent normalization of intraocular pressure, the electroretinogram tends to show a moderate increase in amplitude.

Visual evoked potentials already in the early stage of glaucoma alter their amplitude-time characteristics across the entire range of spatial frequencies, reflecting the state of retinal ganglion cell axons. As the disease progresses, latency increases and amplitude decreases, and by the absolute stage of glaucoma, visual evoked potentials are no longer recordable. With persistent compensation of intraocular pressure, stabilization and subsequent partial restoration of the amplitude-time characteristics of visual evoked potentials occur.

Electrophysiological data are particularly important when visual acuity cannot be assessed due to the child's age and in the presence of optical media opacities when posterior pole structures cannot be visualized.

When evaluating electrophysiological test results in patients with secondary glaucoma, possible indicator changes due to the underlying disease should be considered.

Comments: Ocular ultrasound biometry (A-scan or echobiometry) allows determination of the anteroposterior diameter of the eyeball, anterior chamber depth, and lens thickness, which is important in the comprehensive assessment of glaucoma progression and, in some cases, in determining the pathogenetic mechanisms of intraocular pressure elevation.

Ultrasound examination of the eyeball makes it possible to assess the state of the internal structures of the eye (position of coats, lens, vitreous body state, etc.), which is especially relevant when refractive media are opaque.

Ultrasound scanning of the anterior segment of the eye is performed when it is necessary to obtain a detailed image of the structures of the anterior segment of the eye (especially important in case of corneal opacity), the iridocorneal angle, and the posterior chamber. This allows for measuring the thickness of the sclera, cornea, iris, ciliary body, lens, anterior chamber depth, and the size of the iridocorneal angle (degrees), as well as determining the presence, structure, and dimensions of pathological formations of the anterior segment of the eye, etc. In secondary glaucoma in children, changes may occur in the thickness and structure of the cornea, the thickness, structure, and position of the iris, the dimensions of the iridocorneal angle, the size and position of the lens, the position of the intraocular lens, and the structure, size, and position of the ciliary body, among others. Analysis of the identified changes helps to clarify the cause of development and formulate optimal management tactics for secondary glaucoma.

2.5 Other Procedures

Not used in secondary glaucoma in children.

3. Treatment, including drug and non-drug therapies, diet therapy, and pain management

Treatment of children with secondary glaucoma is carried out using hypotensive medical drugs, laser methods, and surgical procedures.

3.1 Medical hypotensive treatment

Comments. Currently, a wide range of anti-glaucoma drugs is available in Russia. The mechanism, efficacy, and potential side effects of their action are presented in Table 6.

Table 6.

Medical agents for the treatment of glaucoma

However, currently only a portion of hypotensive drugs is approved for children under one year of age. The main registered medicinal products and their age restrictions are presented in Table 7.

Table 7.

Age restrictions for the prescription of the most common hypotensive drugs in the Russian Federation

Combined anti-glaucoma drugs are not approved in childhood and are used under strict indications.

Hypotensive therapy is prescribed immediately after elevated IOP is detected. When choosing drugs, it is necessary to consider their efficacy, the child's age, potential side effects, potential cost, availability, and the preferences of the patient (the patient's parents).

It is necessary to strive to reduce IOP to the "target" level (Table 2).

Main principles of hypotensive therapy:

1. Treatment should begin with monotherapy. The drugs of first choice, depending on the clinical situation, are carbonic anhydrase inhibitors, β-blockers, or prostaglandin analogues. In patients with post-uveitic glaucoma, the use of miotics is contraindicated, and prostaglandin analogues are prescribed only in the absence of active inflammation.

2. If the first-line drug is ineffective, it must be replaced with a drug from another pharmacological group.

3. If monotherapy is insufficient, a combination of drugs or combination drugs should be prescribed.

4. During treatment, it is necessary to carefully monitor the child's general and local status for early detection of potential side effects of therapy.

Efficacy indicators:

1. Maintaining IOP within the optimal (target) level.

2. Absence of a tachyphylaxis (wearing-off) effect over a long period.

3. Minimal systemic impact, minimum side effects.

Local hypotensive drugs are used as an independent type of therapy, as well as during the preparation of the child for surgery and, in a number of cases, when the hypotensive effect of the intervention is insufficient.

As an independent treatment modality, hypotensive therapy is used predominantly in cases of open-angle and mixed (with the presence of goniosynechiae) forms of glaucoma; at the same time, normalizing IOP for more than 5 years is achieved in 30–50% of cases [24].

3.2 Medical neurotrophic treatment

Comments. Ischemia of the optic nerve, as well as stretching of the membranes and compressive pressure on the retina and choroid in glaucoma, leads to apoptosis of the neuronal elements of the visual system.

For neurotrophic treatment, drugs that affect peripheral circulation and improve microcirculation are used: other psychostimulants and nootropic drugs (N06BX), other drugs for the treatment of nervous system disorders (N07XX), angioprotectors (C05), drotaverine** (A03AD02), papaverine (A03AD01), and multivitamins in combination with other agents (A11A). Therapy should be carried out regularly 2 times a year.

3.3 Surgical Treatment

Comments. Surgical treatment is indicated in cases of medically uncompensated glaucoma in patients with open-angle and mixed (with the presence of goniosynechiae) forms of glaucoma, as well as in pupillary block glaucoma, phacogenic glaucoma, malignant glaucoma, and in some cases in glaucoma associated with refractory hyphema or hemophthalmus [21].

Methods of surgical treatment for secondary glaucoma in children include 3 directions:

• restoration of aqueous humor outflow pathways;

• reduction of aqueous humor production;

• optic-reconstructive interventions to restore normal intraocular circulation of aqueous humor

The choice of surgical intervention is determined by:

• the level of initial and "target" IOP;

• the nature of outflow retention (etiopathogenetic form of glaucoma);

• anamnestic data on previous laser and/or surgical interventions and their efficacy;

• technical capabilities, experience, and preferences of the surgeon

Goniotomy. A16.26.067. According to a number of studies, it is effective in uveal and aphakic glaucoma [1, 11, 27, 31, 32, 39, 42, 43, 45, 50, 56, 61].

The stages of surgical treatment include corneal paracentesis and injection of a viscoelastic into the chamber. Next, using a goniotomy knife inserted into the anterior chamber, the tissue covering the trabecular meshwork and the trabecular meshwork itself on the opposite side of the chamber are destroyed by 100⁰ – 110⁰ (within the visualization range of the gonioscope). After a successful manipulation, the aqueous humor drains into Schlemm's canal. In case of failure, the manipulation can be repeated. Potential complications of the surgery include hyphema, cyclodialysis, iridodialysis, peripheral anterior synechiae, and cataract.

Trabeculotomy. A16.26.069 The surgery can be used to treat various types of secondary glaucoma in children – aphakic, post-uveitic, etc. [1, 11, 12, 32, 43, 45, 56, 57, 60].

Trabeculotomy can be performed using metal probes – trabeculotomes, or using a suture or a microcatheter with an illuminated atraumatic tip along a 360-degree circumference.

Standard trabeculotomy. After a conjunctival incision, a scleral flap half the thickness of the sclera is dissected. Schlemm's canal is located, opened radially, and the working probe of the trabeculotome is inserted into the opening as far as the probe's curvature allows, and by rotating it toward the anterior chamber, it is extracted using the "break-and-withdraw" principle.

360-degree suture trabeculotomy. During the surgery, a 6/0 polypropylene suture with a rounded tip melted by means of a thermal cautery is used. The suture is slowly advanced within the lumen of Schlemm's canal using anatomical forceps, and a gonioscope is used to control its position. After passing it through, the proximal and distal ends are brought out through a scleral incision and pulled in opposite directions using needle holders, thereby performing a 360-degree trabeculotomy. Instead of a polypropylene suture, a microcatheter with an illuminated tip can also be inserted into Schlemm's canal for better visualization of the catheter as it advances within the canal.

Possible complications of trabeculotomy include hyphema, serous or hemorrhagic ciliochoroidal detachment, iridodialysis, cyclodialysis, Descemet's membrane detachment, and zonular detachment.

Sinustrabeculectomy (trabeculectomy) A16.26.070 is a fistulizing surgery often performed as the primary operation for glaucoma of various etiologies in children [1, 4, 5, 8, 10, 11, 12, 32, 34, 38, 40, 45, 47, 52, 56]. The goal of the surgery is to create a bypass outflow pathway for aqueous humor by forming a corneoscleral fistula.

Surgical technique. The conjunctival incision is made 6 mm from the limbus, after which the conjunctiva is bluntly dissected as far anteriorly as possible. In primary surgery, the incision is located superiorly from 11 to 1 o'clock. A scleral flap is formed, most frequently U-shaped, measuring 4 mm at the limbus and 3 mm from the limbus, with a thickness of 1/2 to 2/3 of the sclera. Next, side radial incisions are made with a blade in the trabecular zone area up to the entry into the anterior chamber, and Vannas scissors are used to connect these incisions, outlining a rectangular section of trabecular tissue. After the fistula is formed, the iris may prolapse into it, which facilitates iridectomy. It is grasped with forceps and excised in the area above the fistula. Iridencleisis (A16.26.061) can be performed; in this procedure, the iris at the root is not excised, but formed into a flap with its base at the limbus, which is brought out under the scleral flap. Then, the scleral flap is fixed to its bed with interrupted sutures, and a suture is placed on the conjunctiva.

The cause of failures, especially in the long-term period, is postoperative episcleral fibrosis of the filtration zone, which is particularly pronounced in childhood. Intraoperative use of antimetabolites #fluorouracil**, #mitomycin** significantly improves the long-term results of trabeculectomy, but is fraught with serious complications—thinning of the filtering bleb, persistent excessive hypotony, blebitis, and endophthalmitis.

Possible complications of the surgery include hypotony, shallow anterior chamber syndrome, hyphema, ciliochoroidal detachment, macular edema, formation of anterior and/or posterior synechiae, encapsulation of the filtering bleb, and, extremely rarely, retinal detachment and endophthalmitis.

Non-penetrating deep sclerectomy (A16.26.117, A16.26.117.001) – is a type of trabeculectomy in which the inner wall of Schlemm's canal and a narrow strip of the peripheral cornea down to Descemet's membrane are excised beneath a superficial flap, meaning the anterior chamber is not entered, and IOP filtration occurs through the trabeculo-Descemet's membrane [1, 12, 35, 40]. The advantage of the procedure is the low incidence of intraoperative complications such as hyphema, ciliochoroidal detachment, and expulsive hemorrhage, as well as a lower risk of postoperative hypotonia and associated complications (macular edema, ciliochoroidal detachment, choroidal hemorrhages, cataract progression). The disadvantage is poor filtration through the trabeculo-Descemet's membrane in the presence of goniosynechiae in the surgical area, for example, in post-uveitic glaucoma.

The advantage of combining trabeculotomy with trabeculectomy is two separate mechanisms for increasing aqueous humor outflow—through the trabecular meshwork and through the trabeculectomy fistula. However, excessive filtration and hypotony are not observed, and IOP can remain normal even if one of the pathways ceases to function [1].

Antiglaucoma drainage implantation A16.26.130 is indicated for refractory glaucoma (when other interventions are ineffective), for glaucoma associated with aphakia and aviria, and in other situations where uncontrolled hypotony in the early postoperative period is fraught with ciliochoroidal detachment and other complications. Drainage surgery may also be the treatment of choice in cases where filtering surgeries are known to be ineffective—with pronounced changes in the anterior segment of the eye or obliteration of the anterior chamber angle [1, 4, 8, 10, 11, 12, 31, 32, 33, 36, 44, 45, 48, 50, 55, 56, 58, 59].

Variants of antiglaucoma drainage devices:

• tubular drainage systems that provide fluid outflow from the anterior chamber (325010 – Glaucoma treatment shunt***), which are subdivided into valveless (single-plate and double-plate drains) and valved drains. The advantage of valved drains is the restriction of fluid flow using a unidirectional valve, which reduces the risk of postoperative hypotony.

• drains that prevent excessive scarring (scleroscleral and scleroconjunctival) and prolong passive fluid flow from the anterior chamber (collagen antiglaucoma drain).

The surgical technique for implanting a tubular drainage system does not differ from that in adults, but must be performed taking into account the anatomical features of the pediatric eye, especially when its size is increased due to glaucoma. A conjunctival flap is formed, based at the fornix in the selected quadrant, and the conjunctiva is bluntly dissected down to the sclera. The valve platform is placed in the selected quadrant and fixed to the sclera with non-absorbable 7-0 or 9-0 suture material further 8 mm from the limbus, in order to reduce fibroplastic reactions, the source of which is Tenon's capsule cells. In a child's small orbit, to facilitate fixation of the platform in the appropriate position of the implant, performing a canthotomy is indicated. Positioning the tube in the vitreal cavity is possible only after a subtotal vitrectomy, since remnants of the vitreous body can be pulled toward the tube opening and block it.

To prevent erosion through the conjunctiva, the extraocular part of the tube is covered with preserved sclera, cornea, or pericardium.

Possible complications of the surgery include anterior displacement of the tube with its contact with the cornea, tube retraction, iris retraction toward the tube leading to a change in pupil shape, conjunctival erosion with tube extrusion, impaired mobility of the eyeball, diplopia and gaze restriction, obstruction of the drainage tube by blood, fibrin, lens capsule, or vitreous body, hyphema, ciliochoroidal detachment, encapsulation of the filtering bleb, and, extremely rarely, retinal detachment and endophthalmitis.

In case of encapsulation or scarring of the filtering bleb after fistulizing surgeries or antiglaucoma drainage implantation, revision (needling) of the filtering bleb may be performed (A16.26.120.001, A16.26.120.002).

Cyclodestructive procedures are aimed at cause destruction and atrophy of the ciliary body [1, 11, 12, 26, 30, 38, 41, 45, 56]. Currently, the most frequently used method is laser cyclophotocoagulation, for which several approaches (transscleral, transpupillary, intraocular) and several types of lasers have been proposed—Nd:YAG laser, diode semiconductor laser. The diode laser (wavelength 809 nm) has a potential advantage over the YAG laser due to greater absorption by the melanin of the pigmented epithelium of the ciliary body while well preserving other structures through which the laser beam passes. Consequently, less energy is required to achieve histological changes in the ciliary body. The most commonly performed procedure is contact diodelaser transscleral cyclophotocoagulation A22.26.018.

The surgery is typically performed for severe refractory glaucomas when angle, fistulizing, and drainage surgery have failed or surgery is not feasible due to scarring of the conjunctiva, as well as in eyes with a poor functional prognosis.

The treatment energy and the number of burns applied vary depending on the initial IOP level and the degree of iris pigmentation (as an indirect indicator of ciliary process pigmentation). A total of 15–20 applications are made 1.5 mm from the limbus with a perpendicular position of the probe and slight circular indentation, avoiding the superior quadrants. The power and exposure time for the diode laser are 0.5–1.0 W and 0.5–2 s, respectively, starting from minimum values and gradually increasing the radiation dose. If an acoustic snap occurs at the moment of coagulation (pop-corn effect), the power must be reduced to minimize the risk of excessive trauma to the ciliary body.

Possible complications of the surgery include iridocyclitis, hyphema, hemophthalmus, corneal erosion, pupil deformation, and hypotony up to subatrophy of the eyeball. At the same time, careful titration of laser radiation parameters minimizes the number of such complications.

A less traumatic and safer method is micropulse laser transscleral cyclophotocoagulation, which, unlike continuous-wave cyclocoagulation, has two cycles: "on" and "off". During the "off" cycle, the areas of the ciliary body that have been exposed to thermal impact cool down, which helps protect them from excessive thermal damage. The hypotensive effect is achieved through gentle thermal damage to the ciliary body, reduction of aqueous humor secretion, and enhancement of uveoscleral outflow. The method avoids excessive irreversible damage to the ciliary body and, in addition to indications for standard diode laser cyclocoagulation, can be used as a primary intervention in children with high visual functions or in early uncontrolled IOP after angle, fistulizing, or drainage surgeries [12, 37, 54].

Postoperative scarring is complete within 2–3 weeks; if indicated, repeat interventions can be performed at an interval of at least 1 month.

In phacogenic glaucoma, the first-line treatment indicated is the removal of the dislocated, swollen, or damaged lens (A16.26.092.002 Removal of dislocated lens, A16.26.092.004 Removal of lens masses, A16.26.092.005 Lensectomy). In a number of cases, the surgery makes it possible to achieve IOP compensation. If glaucoma is not compensated, one of the antiglaucoma surgeries should be performed (depending on the clinical situation: fistulizing, antiglaucoma drainage implantation, cyclodestructive).

In glaucoma caused by pupillary block, urgent laser (A22.26.005) or surgical (A16.26.060) iridectomy is performed [1, 4, 5, 12, 28, 29, 53], which, in the presence of peripheral anterior or posterior synechiae, can be supplemented with laser synechiolysis (A22.26.020) or, in the case of surgical intervention, anterior chamber angle reconstruction (A16.26.146). In malignant glaucoma in pseudophakic or aphakic eyes, urgent laser hyaloidotomy is performed; in phakic eyes, A16.26.092.005 Lensectomy or pars plana anterior vitrectomy A16.26.089.001 combined with hyaloidotomy and iridectomy is performed.

4. Medical Rehabilitation and Sanatorium-Resort Treatment

Comments. Therapy should be administered regularly twice a year. The treatment regimen may include physiotherapeutic methods: electrophoresis and magnetophoresis with neurotrophic and vasodilating drugs, percutaneous electrical stimulation of the optic nerve (Table 8).

Table 8.

Physiotherapeutic rehabilitation methods

Contraindications to neurotrophic therapy:

1. Unstable compensation of the glaucomatous process.

2. Inability to regularly monitor IOP.

3. Severe concomitant general somatic pathology.

4. Intolerance to prescribed medications.

May be included in treatment regimens:

• Bioresonance therapy in reflexology — treatment using endogenous and exogenous electromagnetic fields.

• Exposure to visible range radiation through the visual analyzer (color pulse therapy) according to T.P. Teterina's method

• Reflexology — acupuncture

• Manual therapy

Maintenance therapy courses should be performed regularly twice a year.

For initial dystrophic corneal changes, keratoprotective gels (dexapanthenol S01XA12) and vitamin-enriched solutions (tauriu S01XA) are used. For total stromal opacities, conservative treatment is ineffective. These cases may be an indication for keratoplasty (provided the glaucomatous process is compensated and the functional prognosis is favorable).

Functional treatment aimed at managing amblyopia through ametropia correction and pleoptics is essential. In children with secondary glaucoma, myopia is more frequently detected, often of moderate and high degrees, which must be corrected.

5. Prevention and Dispensary Observation

Comments. Possible etiopathogenetic risk factors and clinical manifestations of secondary glaucoma are described in sections 1.2 and 1.6. Examinations are performed at least once every 3 months.

Comments. Children with suspected secondary glaucoma or a confirmed diagnosis are placed on the outpatient follow-up register with examination frequencies according to Table 9.

Table 9.

Frequency of ophthalmological dispensary observation for children with glaucoma

All children undergo a comprehensive examination, including assessment of the anterior and posterior segments of the eye, IOP measurement, determination of refraction and visual functions: visometry, refractometry, ophthalmotonometry, automated perimetry, biomicroscopy of the eye, ophthalmoscopy/fundus biomicroscopy, and, if necessary, optical imaging of the retina, optic nerve head, and nerve fiber layer using a computer analyzer (optical coherence tomography, OCT)

6. Organization of Medical Care

Medical care for patients with secondary glaucoma and suspected this condition is provided in accordance with the "Procedure for the provision of medical care to children with diseases of the eye, its adnexa and orbit", approved by Order of the Russian Ministry of Health No. 442n dated October 25, 2012.

Diagnosis of secondary glaucoma is performed by an ophthalmologist, who identifies risk groups for developing secondary glaucoma, suspected secondary glaucoma, and manifest disease among patients with ocular pathology. Children at risk of developing secondary glaucoma (e.g., receiving systemic glucocorticoids) are also referred for consultation with an ophthalmologist by district pediatricians and general practitioners (family physicians). The ophthalmologist performs a comprehensive examination, determines the treatment strategy, and prescribes drug therapy when indicated. If diagnostic procedures require anesthesia, children are referred to the pediatric ophthalmology department.

If there are indications for surgical treatment in a child with a confirmed diagnosis of glaucoma, such treatment is carried out in a pediatric ophthalmology inpatient setting. After receiving inpatient medical care, children are referred to the pediatric ophthalmology clinic for further dispensary observation by an ophthalmologist.

7. Additional Information

The prognosis of secondary glaucoma in children is determined by its etiology, timeliness of diagnosis, and the success of conservative and surgical treatment. Predictors of a good functional prognosis are a low baseline level of intraocular pressure, its stably normal values during conservative treatment, or no need for hypotensive therapy after surgery.

Predictors of a poor functional prognosis include: a refractory course of glaucoma, as well as a long duration of the disease.

Criteria for Evaluating the Quality of Medical Care

Table 10.

Criteria for Evaluating the Quality of Medical Care

References

Appendix A1. Working Group Composition

1. Lyudmila A. Katargina – Group Leader, Chief freelance pediatric ophthalmologist of the Russian Ministry of Health, Deputy Director for Research at the National Medical Research Center of Eye Diseases named after Helmholtz of the Russian Ministry of Health, Head of the Department of Pediatric Eye Pathology, Professor, MD, Moscow;

2. Arestova Nataliya Nikolaevna – Leading Researcher, Department of Eye Pathology in Children, National Medical Research Center for Eye Diseases named after Helmholtz of the Russian Ministry of Health, Associate Professor, MD, Moscow;

3. Brzheskiy Vladimir Vsevolodovich – Head of the Department of Ophthalmology, Saint Petersburg State Pediatric Medical University of the Russian Ministry of Health, D.Sc. (Medicine), Professor. Saint Petersburg;

4. Denisova Ekaterina Valerievna – Senior Research Associate, Department of Pediatric Ophthalmology, National Medical Research Center for Eye Diseases named after Helmholtz of the Russian Ministry of Health, Ph.D. (Medicine), Moscow;

5. Panova Anna Yurievna – Researcher, Department of Eye Pathology in Children, National Medical Research Center for Eye Diseases named after Helmholtz of the Russian Ministry of Health, PhD, Moscow;

6. Sadovnikova Nataliya Nikolaevna – Head of the Ophthalmological Department of the Clinic, Saint Petersburg State Pediatric Medical University of the Russian Ministry of Health, Ph.D. (Medicine), Associate Professor. Saint Petersburg.

Conflict of interest: none.

Appendix A2. Methodology for Developing Clinical Guidelines

Methods used for evidence collection/selection: electronic database searches; analysis of current scientific developments on glaucoma in Russia and abroad; synthesis of practical experience of Russian and foreign colleagues.

The preliminary version of these guidelines was reviewed by independent experts who commented on the accessibility and interpretability of the evidence underlying the guidelines for practitioners and patients.

The comments received from experts were carefully systematized and discussed by the chair and members of the working group. Each point was discussed, and appropriate changes were made to the guidelines.

In these clinical guidelines, all data are ranked by level of reliability (evidence) depending on the quantity and quality of studies on the issue.

Target audience for these clinical guidelines:

• Ophthalmologists;

• Pediatricians (Family Physicians)

Table 1. Levels of Evidence (LoE) grading scale for diagnostic methods (diagnostic interventions)

Table 2. Scale for grading levels of evidence (LE) for prevention, treatment, and rehabilitation methods (preventive, therapeutic, and rehabilitative interventions)

Table 3. Scale for assessing levels of evidence (LE) for prevention, diagnostic, treatment, and rehabilitation methods (preventive, diagnostic, therapeutic, and rehabilitative interventions)

Procedure for updating clinical guidelines.

The clinical guidelines update mechanism provides for their systematic revision—at least once every three years, as well as upon the emergence of new evidence-based data regarding the diagnosis, treatment, prevention, and rehabilitation of specific diseases, or the presence of justified additions/comments to previously approved clinical guidelines, but no more frequently than once every 6 months.

Appendix A3. Reference Materials

These clinical guidelines were developed taking into account the following documents:

1. "Procedure for Providing Medical Care to Children with Diseases of the Eye, Its Adnexa and Orbit", approved by Order of the Ministry of Health of the Russian Federation No. 442n dated October 25, 2012.

2. International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) (World Health Organization) 1994.

3. Nomenclature of Medical Services (Ministry of Health and Social Development of the Russian Federation) 2017.

4. Federal Law No. 323-FZ of November 21, 2011, "On the Basics of Protecting Public Health in the Russian Federation."

5. List of Vital and Essential Medicines for Medical Use for 2024. Order of the Government of the Russian Federation No. 2406-r dated October 12, 2019 (as amended on April 16, 2024) "On Approval of the List of Vital and Essential Medicines, as well as Lists of Medicines for Medical Use and the Minimum Assortment of Medicines Required for the Provision of Medical Care."

6. Order of the Russian Ministry of Health No. 143n dated March 27, 2024, on the approval of the classification of natural medicinal resources specified in paragraph 2 of Article 2.1 of Federal Law No. 26-FZ of February 23, 1995, "On Natural Medicinal Resources, Health Resorts, and Therapeutic Areas," their characteristics, and the list of medical indications and contraindications for sanatorium-resort treatment and medical rehabilitation using such natural medicinal resources. https://normativ.kontur.ru/document?moduleId=1&documentId=468782#h614

Appendix B. Physician Action Algorithms

Appendix C. Patient Information

Secondary glaucoma is a severe condition that is one of the main causes of blindness, low vision, and visual impairment in children. The success of secondary glaucoma treatment largely depends on early detection of the disease and timely initiated therapy.

If treatment is not started in a timely manner, the disease progresses rapidly and leads to irreversible changes in the eyeball. In late stages of the disease, even after surgical treatment, the chances of a successful outcome are significantly reduced. Children with suspected secondary glaucoma or a confirmed diagnosis are placed on dispensary follow-up at the outpatient clinic. In case of suspected secondary glaucoma, the child must be examined, and if the diagnosis is not ruled out, examinations are repeated 3–4 times at least once every 3 months. A child with a confirmed diagnosis and normalized pressure must be seen by an ophthalmologist at least once every three months. Following surgical treatment, the first follow-up examination should be performed no later than 1 week later, and subsequently, depending on the clinical course, once every 1–3–6 months.

An urgent visit to an ophthalmologist is necessary if any of the following symptoms appear: eye redness, photophobia, pain, decreased and/or blurred vision, visual field loss, impaired color perception, changes in iris color, pupil size, and pupil shape.

It is essential to strictly follow all prescriptions and the recommended frequency of examinations by an ophthalmologist.

The patient (the patient's parents) must be informed about potential side effects of therapy and urgently consult an ophthalmologist if they develop.

In cases of irreversible blindness or low vision, the patient (the patient's parents) must have complete information regarding social, psychological, and vocational rehabilitation options.

Appendix G. Assessment Scales, Questionnaires, and Other Evaluation Tools

Not applicable.